The Heroes of Olympus go to Hogwarts
by Little Doctor
Summary: The seven plus Nico, Reyna, and Lou Ellen go to Hogwarts to protect Harry Potter and destroy horcruxes.
1. Chapter 1

**A/N: So, this is my first Heroes of Olympus and Harry Potter crossover. I hope it goes well!**

**Disclaimer: I only own the plot.**

* * *

**Percy's Point of View**

* * *

I was sitting on the beach, just watching the waves roll and making miniature horses out of the water. Somehow, this calmed me down as much as Annabeth. After T-t-tarturus, things that could calm me down were scarce. The Giant war was over. It had been for three weeks now. Coach Hedge came trotting down the beach, "JACKSON! Get to the big house! On the double!"

"What for?" I called.

"Chiron wants you! Now did you hear me? ON THE DOUBLE!"

Coach Hedge ran off, no doubt to care for his baby saytr or something. Laughing at Coach's antics, I jogged to the Big House.

When I got there, everyone except Chiron was in there. Travis and Connor were pickpocketing Katie, who was growing plants in Clarisse's hair. Lou Ellen was rearranging everyone's faces, Piper was charmspeaking random people to act like monkeys, Will was playing ping pong with Pollux, but using a tennis ball so every thirty seconds or so, the ball would hit somebody. Butch was creating rainbows. Leo was tinkering with whatever was coming out of his tool belt, Nico was just leaning in the shadows. Clovis was snoring, Freya, the head counselor for the Tyche cabin was betting with Rian, the head counselor for the Hebe cabin on how many pencils they could fit in Clovis's nose. Nyra, head counsoler for the Nike cabin, was arm-wrestling Parker, who was the head counselor for the Nemesis cabin, and my beautiful girlfriend, Annabeth, was reading a translated copy of _The Rise and Fall of the Roman Empire_. I settled down, and began splashing people with water.

Chiron came in with Thalia and the tennis ball hit him on his torso, everyone instantly became silent.

"Ouch, Will, Pollux kindly refrain from playing ping pong with the tennis ball right now. Lou Ellen, please put everyone's faces back to normal. Travis, give Katie back her things. Piper, kindly tell Connor to act like a normal human being. Freya, Rian, I'm sure we would all appreciate if you took all of the pencils out of Clovis' nose and woke him up. Parker, Nyra, time to stop arm-wrestling. Percy, all of that water can go back in the lake. Annabeth, Leo, we're going to start the meeting now."

As soon as we all did as Chiron instructed, he began.

"Alright, now you are all probably wondering why I called you write now. The reason is ... there is another world out there. Gods and demigods aren't the only different beings on Earth. There are ... witches and wizards."

There was dead silence. Then Leo spoke up.

"You mean, people who ride on broomsticks, wear pointy hats, and say Bippity Boppity Boo?"

"No Leo, there are people who do magic. Yes they do ride broomsticks, they do sometimes wear pointy hats. But they don't say Bippity Boppity Boo."

"Oh! I know them!" Lou Ellen exclaimed, "Once upon a time, mom blessed some mortals with the power to do magic. Except they need sticks to channel their magic!"

"Correct Lou Ellen," Chiron said, "And they have spread and multiplied since, mostly in Europe. However, there was a wizard who went bad. He began killing people left and right, and gained a group of followers that call themselves Death Eaters."

Chiron shouldn't have said that. As soon as the words "Death Eaters" left his mouth. The giggles started.

"Who would want to eat Thanatos!" Connor managed to get out between laughs.

"Guys! This is serious! My father says that they have murdered hundreds of innocent people!" yelled Nico.

That sobered everyone up and Chiron quickly took the opportunity to continue his speech.

"So, the wizard who went bad tried to kill a little boy who, from a prophecy was destined to be his fall, however, the killing curse backfired and killed _him _or so people say. He was never dead, but made horcruxes. Which split his soul into pieces. He made seven of them. Now, he has a full body and is planning to kill Harry Potter, the little boy whom he tried to kill as a baby. I need Percy, Nico, Annabeth, Piper, Leo, Thalia, and Lou Ellen to pose as American Exchange students."

Immediately protests rang out.

"Why them?"

"This isn't fair."

"Why can't we go."

"Everybody quiet down!" Chiron shouted over the roar of noise.

"The reason only Percy, Nico, Annabeth, Piper, Leo, Thalia, and Lou Ellen can go is because we can't have too many exchange students. My good friend, Albus Dumbledore,"

Snorts came from everybody.

Chiron continued, clearly irritated, "As I was saying. My good friend, Albus Dumbledore, has stated too send only a few students not to draw attention. Plus, Frank, Jason, Hazel, and Reyna who are being debriefed right now, are coming from Camp Jupiter. They should be coming from the portal very soon. Annnnd, I also have a job for the rest of you."

Let me explain about the portal bit. When Reyna, Nico, and Coach Hedge came with the Athena Parthenos, the two camps came together with peace. The Hecate/Trivia people had constructed portals so we didn't have to travel cross country to get to the other camp.

Right on cue, Frank, Hazel, Jason, and Reyna stumbled in. Actually, Frank and Jason stumbled in. Reyna held herself like a Praetor (which she was) and Hazel just walked in calmly.

"Okay, we're ready," Jason breathed.

"Excellent!" a new voice cried.

Hazel whirled around and knelt.

"Lady Hecate."

Quickly, we all got to our knees.

"Rise heroes. I have come to bless you and turn Percy, Nico, Annabeth, Piper, Frank, Jason, Hazel, Reyna, and Lou Ellen to fifteen years old. Thalia is already fifteen so no age changing needed. For her."

"Lady Hecate, when will we change?"

"Right ... now!"

I didn't feel any smaller, but I looked at Leo, he was back to his scrawny stage. Frank was back to his "Chinese baby man" stage as Arion put it. And Hazel looked older.

I felt a tingling sensation. I felt like I could swim to England and back!

"Whoa," said Piper, "I feel short."

"Now, here are your tickets Annabeth," Hecate gave Annabeth the plane tickets.

Wait plane tickets? Oh no! We're going on a plane!

"Umm, Lady Hecate? I can't go on a plane, Uncle Z. is going to blast me out of the sky," I stammered.

"Me too," Nico stuttered looking paler then ever.

"Not to worry, Zeus has given Hazel, Percy, and you permission to go in his domain for the trip there and back. He did state not to do it again though. When you get off the plane, look for a man with red hair holding a sign that says your names in Greek and Latin on it. He will say 'A storm's coming' and you will say 'Penguin's don't fly, Phoenix's do' back," Hecate told us. She snapped her fingers, "I have just deposited a suitcase full of things you will need at the school, a wand, robes, and textbooks. Everyone close your eyes now."

We all did and with a flash of light, Hecate disappeared.

There was a moment of awkward silence.

"What's the school's name?" asked Rian.

Chiron sighed, "Hogwarts."

No one bothered to stifled there giggles this time. There were large hoots of laughter this time.

"What's the evil wizard's name?" asked Freya.

"Voldemort."

This combined with Hogwarts made all of the usually dignified girls break down into laughter.

* * *

Later today, I stepped into my cabin. Sure enough, there was a suitcase sitting on my bunk. I opened mine up. There was a thin box on the top, I opened it up. Inside was a stick. I was expecting something more impressive than that. A piece of paper lay under it. It read 'Wood from an underwater mangrove tree, and a feather from Pegasus'

* * *

The next day, we met by Thalia's pine. I was the last there, so I was met by Thalia exclaiming, "Pine! My wand is made of pine!"

Pine. How ironic. I stifled a laugh.

* * *

Argus dropped us off at the airport. My knuckles were white as I boarded the death trap. Nico looked paler then ever.

Good for me! I would be spending three hours on a metal contraption with 9 ADHD other demigods, and one lactose-intolerant demigod.

Jason looked as happy as could be.

_Please don't knock me out of the sky uncle, I promise to sacrifice to you for a month. Please don't blast me out of the sky. _I prayed.

* * *

**Three Hours Later ...**

* * *

I practically ran down the stairs, I kissed the ground.

"Thank you, thank you, thank you, thank you for not blasting me out of the sky uncle. Thank you, thank you, thank you," I muttered in Ancient Greek. I was getting strange looks from passengers however, so I stopped.

"C'mon Seaweed Brain," said Annabeth, "I think I found our host." I looked where she was pointing, and there was a red-haired man dressed in an flamboyant outfit holding a cardboard sign that said in Ancient Greek:

_Perseus Jackson_

_Annabeth Chase_

_Thalia _

_Jason Grace_

_Reyna _

_Hazel Levesque_

_Frank Zhang_

_Leo Valdez_

_Piper McLean_

_Lou Ellen_

_Nico Di Angelo_

"This way!" called Annabeth. We followed her and stopped before the man.

"A storm's coming," the man said.

"Penguins don't fly, Phoenix's do," Annabeth replied. Huh?

"Come along you lot," the man said, "My name's Arthur Weasely."

We followed him to a Ford Angela.

"Come on in."

It was Hazel who voiced what we were all thinking, "Mr. Weasely, I don't think we can all fit."

"Yes we can," Mr. Weasely said.

We were uncertain, but we all piled in. To our surprise, we all had plenty of room.

* * *

After the drive, we arrived at headquarters.

"Read this quickly, then destroy it," Mr. Weasely told us.

_Number 12 Grimwald **(A/N: spell check?)** __Place_

After we all read it, Leo set it on fire to the amazement of Mr. Weasely.

We looked at the space between Number 11 and Number 13. To our awe, a house just appeared.

"Welcome," said Mr. Weasely.


	2. Hogwarts train

**A/N: Thank you for those lovely reviews! And I really don't think I have an excuse for not posting in a long time. Sorry! **

**AriquRmegustaleer : I looked it up, I think it's Grimmauld place.**

**Titania Ocean : Thanks for the spell check! **

**ChildOfHermes : Thank you so much for that review! I promise to continue this story even though the updates might take a bit long because of school. And I am a girl. **

**Macy : I love it that you think this is awesome! Thank you so much!**

**Smiley101 : They aren't going to stay at Grimmuald Place much longer. Thanks!**

**clestiel : Thanks for the spell check! **

**WizardDemigodChildofAthena : Yeah! My favorite books too!**

**Winterlover6 : Thanks!**

**Guest : Thanks!**

**Oh, and by the way**

"_This is people talking in Greek._"

"This is people speaking in English."

"**This is people talking in Latin.**"

**Hazel's Point of View**

* * *

As we walked down the halls, I could feel the incredible amount of precious metals and jewels in this place. It was gloomy and unwelcoming, but so loud here. The riches were calling out to me. I squeezed my eyes shut and blocked it all out. A second later I opened them. Everything was back to normal.

"Hazel? Hazel? Are you all right?" asked Piper.

"I'm fine," I replied.

We walked into a dining room it looked like. Or maybe it was a war counsel. I couldn't tell. Everyone was talking at the same time until Mr. Weasely gave a soft cough. Every eye in the room turned to him.

"Are these Harry's protectors?" growled a man with one regular eye, and another big, and electric blue, spinning in its socket. The effect was sickening, "Doesn't look like much."

"Well, Dumbledore said they are qualified, and if there's one person we can trust, it's Dumbledore," answered Mr. Weasely.

"So, tomorrow is your first day of Hogwarts," a bald man with a dark complexion told us in a deep voice, "I have been informed that one of you possesses Umbrakenisis."

"Here," said Nico.

"Wait!" barked the man with the weird eye, "You are only a child!"

I laughed inwardly. Nico? A child?

"Listen old man, I am NOT a child! I have been through more than you ever have!" Nico growled back. The shadows in the room seemed to darken. I think he also let his ability to create fear slip out as well.

I tapped him on the shoulder, "_Nico! Calm down!_"

Nico whirled around. Slowly, the room felt warmer and looked brighter. The adults looked frightened.

"Okay people," Piper, ever our diplomat said, "We don't want to hurt you. All we're here for is to protect Harry Potter. And please don't insult any of us. We are not children. We have been through war, and in some cases, more than one."

The adults still looked shaken though.

"You will be staying in the attic for now. There are children in this house. They cannot know of you," the bald man said.

"Okay," Annabeth replied.

"I'll shadow travel you up there," Nico said, still fuming.

"Well let's get going!" Leo tried in an attempt to bring up the mood of the room.

We all grabbed hands and Nico pulled us through the shadows. I felt the usual sensation of going so fast you feel like your face is peeling off. As the shadows spit us out, we got a clear view of a GIGANTIC floor. Nico promptly collapsed. Everyone else quickly rushed to choose a bed. Sorry, let me rephrase that. Percy and Leo rushed to choose a bed. Frank and Jason lugged Nico over to one of the closest ones. Piper, Annabeth, Reyna, and I walked like civilized people. In the end, Percy and Annabeth shared a bed, Piper and Jason chose the two beds closest together, Frank and I did the same, and Reyna just went close to the middle with Leo.

* * *

**The Next Day**

* * *

An extremely loud alarm clock woke me up. It was one of those windups Leo had made last night. Mars Almighty, it was so annoying.

I heard Frank stir, "Uhhhhh."

I sat up groggily and tried to shake the sleep from my eyes. Naturally, Leo was up and jumping.

"Everybody up! It is 9:00 in the morning, and the train leaves at 11!" cried Leo.

If the room wasn't soundproofed, our cover would've been blown already.

Thalia blinked twice, then electrocuted Leo as he walked by.

"Valdez," she growled, "you better have had a good reason to wake me up at 9:00 in the morning when the train leaves at eleven other than annoying me!"

With a winning smile, Leo waggled his eyebrows.

"Of course I have a better reason then just annoying you! I was irritating and aggravating you!" he replied cheekily.

Thalia groaned, then got out of her bed, "C'mon. Guess we'd better get up and eat breakfast. Smokes over there isn't going to stop any time soon."

Soon after, everybody except Annabeth and Percy who were still sleeping was dressed.

"Who wants to wake them up this time?" Jason asked.

"One... two... three... NOT IT!" shouted Leo.

"NOT IT!" The rest of us shouted.

"Well, since none of us volunteered, Frank, why don't you do it," Piper asked without putting a drop of charmspeak in her voice.

"Why me?" Frank groaned.

"Well, you could turn into an animal, wake Annabeth up, then scamper away quickly in animal form," Piper told him.

"Well why not Lou?" he asked.

Lou had gone invisible.

Frank looked to me

* * *

in desperation. I shook my head and pointed to Annabeth.

Frank gulped, "Thanks a lot Hazel."

He turned into an hawk owl, quickly pecked Annabeth, then flew at speeds faster than I had previously believed an owl could fly.

Even so, Annabeth still managed to punch Frank in her sleep. Then she shook her head woozily and lightly tapped Percy. It still amazes me how Percy wakes up when Annabeth does it.

Breakfast was a delicious affair of Leo-style tofu and whatever Lou had in her bag (we didn't trust the food in the attic).

* * *

**Piper's Point of View**

* * *

There were all of these trunks at the foot our beds. According to Lou, they contained all of our things needed for Hogwarts. After looking in these, I have confirmed that somebody raided Cabin Ten and dumped my things into this trunk! On the right section of my trunk I have personal items are there as well as some armor. On the left section of the trunk, I have a wand, several textbooks written in Greek, robes, and . . . . . SKIRTS! Oh gods! If this is a traditional school . . . . . TRADITIONAL CLOTHING!

I glanced at Annabeth. She too was staring in horror at the unconventional garment.

At ten forty-five, Nico grabbed Reyna's hand and shadow traveled off. Percy did the same to Annabeth, Jason air traveled with me, and Hazel shadow traveled with Frank. Lou did that weird thing wizards did when they disappear with a pop!

We materialized into a compartment with Luna and Neville.

"Luna!" that was Annabeth jumping up to hug her half-sister. The guys did the weird macho one armed hug thing that guys do with Nev and happy greetings were exchanged all around. Neville was a son of Ceres centurion from the fifth cohort back at Camp Jupiter, I could see how hard it was for him not to salute Percy, Jason, Frank, or Reyna. Luna was from the Athena cabin at Camp Half-blood.

According to Luna, there were three others; Dean, Lavender, and Draco. Dean was a son of Hephastus. Lavender was one of my half-sisters on the Roman side that wasn't a year-rounder. Draco was one of Annabeth's half-brothers.

"There's room in this one, it's just Looney Lovegood, Neville, and some of their friends in here-," I heard somebody say.

My fists clenched. Luna was _not _Looney! She was brave demigod who had survived _two _wars!**  
**

The door to our compartment opened, revealing a girl who could've been Rachel's sister and a scrawny boy that had messy black hair and emerald eyes.

"Hi Luna, is it okay if we take these seats?" the girl asked. Instantly Luna painted a dreamy look on her face and grabbed a magazine lying on the bench that was _so _not like her. She took her time deciding. She nodded.

"_My cover_," she explained. A look of understanding crossed everybody else's face.

"Had a good summer, Luna?" the girl asked.

"Yes," Luna replied dreamily, "Yes it was quite enjoyable, you know. You're Harry Potter."

"I know I am," mini-Percy said.

"Luna, can you introduce us to this duo?" I asked Luna in the politest voice I could manage.

"Oh, this is Ginny Weasely, and this is Harry Potter."  
Muttered hellos were passed around.

"Hi, I'm Piper, this is Frank, Hazel, Reyna, Jason, Percy, Annabeth, Nico, and Lou Ellen. Nice too meet you," I politely said.

That Harry guy tried to shake hands with Nico, who obliged very reluctantly. His sleeve fell down. I think Harry caught sight of his SPQR tattoo. Darn! I could see him stiffen.

* * *

**Sorry for the cliffhanger!**


	3. Chapter 3

**AN: Hey guys! *doges tomato* Erm... Hehe ... I'm really really sorry for the long wait and I have no excuses, you guys were awesome though! I read a review last night, and it really motivated me . . . so here it is.**

Harry's POV

I saw a tattoo on that emo kid- Nico's arm. I know Ginny noticed too- she let out a not-so-subtle gasp. It was absolutely, positively a tattoo. Probably a Death Eater one, although you'd think they'd be more subtle about it. Really, let's just put a snake in skull tattoo on the forearm of every single one of our followers and hope it doesn't get noticed! Why not? I'd take it up with Hermione, who'd be more reasonable than Ron. I glanced at Neville to try to warn him about potential Death Eaters, but he wasn't paying attention. Instead he was making eyes at Lou Ellen, a girl with purple highlights in her hair. She seemed a more than a bit eccentric, as she was drawing a strange symbol that consisted of an owl, trident, and seaweed with a bright pink Darth Vader pen. She was also wearing pants with cats on them. Strange, but not unheard of.

Ginny tugged on my arm and asked, "Well, are we sitting or not?"

I sat down an empty space by Neville, the only one I was not weirded out by. The new kids had already forgotten about us, it seemed. They were all doing their own thing.

"So," Ginny started.

"So what?" asked the guy who looked like me, but without glasses.

"Why are you here? No offense, but there aren't usually new students after first year."

"We're exchange students. Your headmaster and our headmaster got together and decided they wanted to spring us from what was going to be one of our years of hell sch- sorry high school and send us to another prison camp," joked the short guy- Leo. He looked Hispanic and was constantly drumming his fingers on the seats. The blonde girl hit him on the head.

"Owwww," he whined, "What was that for?"

"For insinuating school was a prison camp," she then turned back to her book, which I just noticed was in no language I knew. I wish I had taken Ancient Runes. It probably could have been useful.

* * *

Hermione opened the door, "Thank goodness we found you! This is our second time checking all of the compartments! Where were you?"

Lou Ellen raised her hand, "Well, that may have been my fault. You see, after Harry and Ginny over here stumbled upon this compartment, I placed a timed notice-me not charm on us. You probably would have seen just an empty compartment. Sorry, I needed sleep."

"Is that allowed?" asked Hermione.

"How am I supposed to know?" was the answer she received from the only _slightly_ eccentric girl.

"You should know the rules before you break them," Hermione scolded.

"Hmmmm. Interesting thought, maybe I'll try it someday."

* * *

Third person POV

Everyone got off the train and into a carriage. Hermione, Ginny, Ron, Harry, Neville, and Luna split off from us to have their own carriage and conversation about Thestrals. Leo looked around nervously, "Do you think they'll confiscate Festus?"

Piper whipped her head around to stare at him. Frank choked on his own spit, and Annabeth said . . .

"You brought Festus! Are you crazy?!"

"Hey! Well, sort of, but that's not the point. Do you think they'll let me bring Festus in?"

"Do they have a choice?" Hazel asked, her golden eyes death staring Leo down.

"Well, no, but I want to know what happens if they find him," Leo gulped, "Okay, I know I shouldn't break school rules, but aren't you on Team Leo?"

"That's a good question. Here's one of my own. How are you going to smuggle a giant celestial bronze dragon into a school?!" Hazel hissed, "Even if he's 'tame' he's still an automaton and it's not fair to the actual students if he decides one of them looks like a Greek monster!"

"He's in my tool belt," Leo hid behind Reyna, which was not a good idea. She had an VALDEZ!-don't-smuggle-a-giant-bronze-dragon-into-a-school-or-I-will-let-Aurum-and-Argentum-after-you look on her face. Annabeth looked like she was enjoying Leo being chewed out by the rest of the girls and the boys had a look of pity on their faces.

"Skeleton horses!" Jason nearly shouted.


End file.
